Improvement in mechanical movements



H. K. PORTER.

- MECHANICAL MOVEMENT.

No.186,016. Patented Jan. 9, 1877.

FIG. 3

UNITED STATES PATENT ()FFICE.

HENRY K. PORTER, OF BOSTON, MASSACHUSETTS.

IMPROVEMENT IN MECHANICAL MOVEMENTS.

Specification forming part of Letters Patent No. 186,016, dated January 9, 1877; application filed May 31, 1875.

To all whom it may concern Be it known that I, HENRY K. PORTER, of Boston, in the county of Sufiolk and State of Massachusetts, have invented a new and useful Mechanical Movement, of which the following is a specification:

The object of my invention is to provide a device, tool, or machine, having a series of triangular slides, the sum of whose central angles is equal to three hundred and sixty de grees, all being arranged to move together tangentially, and having always a common and unvarying center with solid boundaries, whereby a variable central aperture of correspending sides may be had.

The invention is illustrated in detail in the accompanying drawings, as embodied in a tap-wrench formed with four of said slides.

Figural is a top or plan view, and showing the dies partially opened. Fig. 2 is a similar view, showing the dies closed. Fig. 3 is a horizontal section taken through the axes of the actuating-screws. Fig. 4 is a transverse section taken on line A B, Fig. 2.

In the drawings, a is the frame, having a recess or internal space, with four equal sides, in which are inserted the dies b, each of which is formed with the four sides 1 2 3 4--line 1 bearing against frame 01., lines 2 and 3 acting against two of the dies, and line 4 serving as a stop when the dies are fully expanded; and the limit of expansion is governed by the location of line 4 relatively between the points of intersection of lines 1 and 2 and 1 and 3.

The actuating-screws cclare threaded in the frame a, as shown in Fig 3, their points acting against the seat 0. (Shown in die b Fig. 3.) The dies or slides 12 and b are shown in this figure as having spacesff cut in them to allow their moving past the screws d e. g g represents a flange or plate formed upon the frame, and upon which the dies rest. his a cap shown partly removed, and which, when in position, holds the dies in place. A'hole in this plate corresponds with holej in. plate g, and allows a free passage for any tool, which is inserted between the dies.

By retracting screw 6 and advancing screw (1 the apex of lines 2 3 meet at a common center, as shown in Fig. 2, and the difference between the internal area of frame a and the aggregate area of dies b is embraced in spaces It.

By reversing the described action of the actuating -screws this open space is transferred, in any desired degree, to the center, as shown at 1, Figs. 1 and 3.

By the combined action of these screws the dies may be locked with the central hole of any desired size, or by the action of screw (1 any properly formed body may be firmly screwed between the dies in the central aperture l.

The handles '5 i, or any other device, may be employed for the manipulation of this invention.

It will be apparent that three, or any desired number, of dies or slides may be employed; and that this invention is susceptible of various uses and modifications.

Instead of the actuating-screws c d other devices may be employed, and the invention may be embodied in lathe or other chucks of all sizes, or for pump-pistons, instruments for demonstrating the largest square contained in any given circle, and for other purposes.

I claim as my invention- 1. A mechanical movement consisting ot'a series of triangular slides,-the sum of whose central angles is equal to three hundred and sixty degrees, arranged to move together tangentially within solid boundaries, and having always a common and unvarying center, whereby a variable central aperture of corresponding sides may be had, substantially as described and shown.

2. The seat 0 formed in the dies by cutting therein the space f, whereby the length of the die is retained, yet it is not obstructed by the actuating-screws, substantially as described and shown.

3. A tap-wrench embodying the described mechanical movement, and provided with the handles 6 i, projecting from the encircling wall of the dies, substantially as described and shown.

HENRY K. PORTER.

Witnesses:

EBEN HUTOHINSON, T. W. PORTER. 

